1. Field
Apparatuses consistent with the present disclosure relate to optical modulators, and more particularly, to optical modulators having reflection layers.
2. Description of the Related Art
In the current market for display devices, three-dimensional (3D) photographing and 3D display are considered to be hot issues, and have been utilized in various fields and in conjunction with various devices such as sensors and game consoles.
Unlike a stereo-type 3D image generation method, a 3D image generation method uses distance as depth information, and accordingly, may be used in conjunction with precise measurement devices or sensors, as well as with 3D displays.
A 3D depth sensor using an infrared (IR) light source adjusts IR transmittance by turning on and off a voltage applied to a transmissive optical modulator and determines a depth measurement based on a difference between transmittances. An absorption rate of the transmissive optical modulator varies depending on whether the voltage is turned on or off.
An optical modulator is used as an image-type distance sensor which photographs an object and precisely measures distances between all points in an image. Such an optical modulator may be utilized in various fields from everyday appliances to military usages, for example, an image-type distance sensor for an autonomous mobile robot, a precise measurement apparatus, safety sensors both inside and outside of vehicles, autofocusing a camera, a sensor for a security closed circuit TV (CCTV), 3D object surface recognition and printing, a broadcasting 3D camera, an endoscope 3D camera, a distance sensor for improving the accuracy of military missiles, etc.